jQuery.validator.addMethod("username", function(value, element) {
	return this.optional(element) || /^[\dA-Za-z\一-\龥\_\＿]+$/i.test(value);
}, "Letters only please"); 

jQuery.validator.addMethod("integer", function(value, element) {
	return this.optional(element) || /^-?\d+$/.test(value);
}, "A positive or negative non-decimal number please");